Synonyms of on guard

on guard

phrase

as in alert

paying close attention usually for the purpose of anticipating approaching danger or opportunity

Since it was hunting season, we wore brightly colored vests and remained on guard while hiking.

Synonyms & Similar Words

• alert
• awake
• vigilant
• on tiptoe
• aware
• watchful
• alive
• on the ball
• attentive
• careful
• on the qui vive
• on the alert
• regardful
• observant
• sensitive
• wide-awake
• cautious
• Argus-eyed
• wary
• tenty
• conscious
• on one's toes
• keen
• open-eyed
• prepared
• sharp
• mindful
• cognizant
• sleepless
• wakeful
• heedful
• ready
• hypervigilant
• hyperalert
• chary
• sharp-eyed
• observing

Antonyms & Near Antonyms

• asleep
• absent
• dreaming
• absorbed
• sleeping
• engrossed
• preoccupied
• distracted
• unaware
• dreamy
• unconscious
• oblivious
• abstracted
• faraway
• careless
• insensible
• dazed
• daydreaming
• unwitting
• unprepared
• heedless
• unmindful
• unwary
• absentminded
• unthinking
• inattentive
• unknowing
• unheeding
• unready

Example Sentences

Recent Examples of on guard

The resulting climate of instability and fear meant church communities were constantly on guard against strangers without and enemies within. — Literary Hub, 28 Sep. 2026

That exemption will be used on guard Eliška Joklová (nee Hamzová), whose third seven-day contract is about to expire. — Mike Cook, Twin Cities, 2 Aug. 2026

Disinformation and misinformation experts who spent years telling the public to be on guard against deepfakes are now trying to convince the public that the McConnell image is real. — David A. Graham, The Atlantic, 15 July 2026